aboutsummaryrefslogtreecommitdiffstats
path: root/arch/parisc/kernel/unwind.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/parisc/kernel/unwind.c')
-rw-r--r--arch/parisc/kernel/unwind.c128
1 files changed, 77 insertions, 51 deletions
diff --git a/arch/parisc/kernel/unwind.c b/arch/parisc/kernel/unwind.c
index 2ef83d78eec4..f329b466e68f 100644
--- a/arch/parisc/kernel/unwind.c
+++ b/arch/parisc/kernel/unwind.c
@@ -13,7 +13,6 @@
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/slab.h>
-#include <linux/kallsyms.h>
#include <linux/sort.h>
#include <linux/uaccess.h>
@@ -117,7 +116,8 @@ unwind_table_init(struct unwind_table *table, const char *name,
for (; start <= end; start++) {
if (start < end &&
start->region_end > (start+1)->region_start) {
- printk("WARNING: Out of order unwind entry! %p and %p\n", start, start+1);
+ pr_warn("Out of order unwind entry! %px and %px\n",
+ start, start+1);
}
start->region_start += base_addr;
@@ -203,26 +203,63 @@ int __init unwind_init(void)
return 0;
}
-#ifdef CONFIG_64BIT
-#define get_func_addr(fptr) fptr[2]
-#else
-#define get_func_addr(fptr) fptr[0]
-#endif
-
static int unwind_special(struct unwind_frame_info *info, unsigned long pc, int frame_size)
{
- extern void handle_interruption(int, struct pt_regs *);
- static unsigned long *hi = (unsigned long *)&handle_interruption;
-
- if (pc == get_func_addr(hi)) {
+ /*
+ * We have to use void * instead of a function pointer, because
+ * function pointers aren't a pointer to the function on 64-bit.
+ * Make them const so the compiler knows they live in .text
+ * Note: We could use dereference_kernel_function_descriptor()
+ * instead but we want to keep it simple here.
+ */
+ extern void * const handle_interruption;
+ extern void * const ret_from_kernel_thread;
+ extern void * const syscall_exit;
+ extern void * const intr_return;
+ extern void * const _switch_to_ret;
+#ifdef CONFIG_IRQSTACKS
+ extern void * const _call_on_stack;
+#endif /* CONFIG_IRQSTACKS */
+
+ if (pc == (unsigned long) &handle_interruption) {
struct pt_regs *regs = (struct pt_regs *)(info->sp - frame_size - PT_SZ_ALGN);
dbg("Unwinding through handle_interruption()\n");
info->prev_sp = regs->gr[30];
info->prev_ip = regs->iaoq[0];
+ return 1;
+ }
+
+ if (pc == (unsigned long) &ret_from_kernel_thread ||
+ pc == (unsigned long) &syscall_exit) {
+ info->prev_sp = info->prev_ip = 0;
+ return 1;
+ }
+
+ if (pc == (unsigned long) &intr_return) {
+ struct pt_regs *regs;
+
+ dbg("Found intr_return()\n");
+ regs = (struct pt_regs *)(info->sp - PT_SZ_ALGN);
+ info->prev_sp = regs->gr[30];
+ info->prev_ip = regs->iaoq[0];
+ info->rp = regs->gr[2];
+ return 1;
+ }
+ if (pc == (unsigned long) &_switch_to_ret) {
+ info->prev_sp = info->sp - CALLEE_SAVE_FRAME_SIZE;
+ info->prev_ip = *(unsigned long *)(info->prev_sp - RP_OFFSET);
return 1;
}
+#ifdef CONFIG_IRQSTACKS
+ if (pc == (unsigned long) &_call_on_stack) {
+ info->prev_sp = *(unsigned long *)(info->sp - FRAME_SIZE - REG_SZ);
+ info->prev_ip = *(unsigned long *)(info->sp - FRAME_SIZE - RP_OFFSET);
+ return 1;
+ }
+#endif
+
return 0;
}
@@ -238,34 +275,8 @@ static void unwind_frame_regs(struct unwind_frame_info *info)
if (e == NULL) {
unsigned long sp;
- dbg("Cannot find unwind entry for 0x%lx; forced unwinding\n", info->ip);
-
-#ifdef CONFIG_KALLSYMS
- /* Handle some frequent special cases.... */
- {
- char symname[KSYM_NAME_LEN];
- char *modname;
-
- kallsyms_lookup(info->ip, NULL, NULL, &modname,
- symname);
-
- dbg("info->ip = 0x%lx, name = %s\n", info->ip, symname);
-
- if (strcmp(symname, "_switch_to_ret") == 0) {
- info->prev_sp = info->sp - CALLEE_SAVE_FRAME_SIZE;
- info->prev_ip = *(unsigned long *)(info->prev_sp - RP_OFFSET);
- dbg("_switch_to_ret @ %lx - setting "
- "prev_sp=%lx prev_ip=%lx\n",
- info->ip, info->prev_sp,
- info->prev_ip);
- return;
- } else if (strcmp(symname, "ret_from_kernel_thread") == 0 ||
- strcmp(symname, "syscall_exit") == 0) {
- info->prev_ip = info->prev_sp = 0;
- return;
- }
- }
-#endif
+ dbg("Cannot find unwind entry for %pS; forced unwinding\n",
+ (void *) info->ip);
/* Since we are doing the unwinding blind, we don't know if
we are adjusting the stack correctly or extracting the rp
@@ -394,9 +405,31 @@ void unwind_frame_init_from_blocked_task(struct unwind_frame_info *info, struct
kfree(r2);
}
-void unwind_frame_init_running(struct unwind_frame_info *info, struct pt_regs *regs)
+#define get_parisc_stackpointer() ({ \
+ unsigned long sp; \
+ __asm__("copy %%r30, %0" : "=r"(sp)); \
+ (sp); \
+})
+
+void unwind_frame_init_task(struct unwind_frame_info *info,
+ struct task_struct *task, struct pt_regs *regs)
{
- unwind_frame_init(info, current, regs);
+ task = task ? task : current;
+
+ if (task == current) {
+ struct pt_regs r;
+
+ if (!regs) {
+ memset(&r, 0, sizeof(r));
+ r.iaoq[0] = _THIS_IP_;
+ r.gr[2] = _RET_IP_;
+ r.gr[30] = get_parisc_stackpointer();
+ regs = &r;
+ }
+ unwind_frame_init(info, task, &r);
+ } else {
+ unwind_frame_init_from_blocked_task(info, task);
+ }
}
int unwind_once(struct unwind_frame_info *next_frame)
@@ -433,19 +466,12 @@ int unwind_to_user(struct unwind_frame_info *info)
unsigned long return_address(unsigned int level)
{
struct unwind_frame_info info;
- struct pt_regs r;
- unsigned long sp;
/* initialize unwind info */
- asm volatile ("copy %%r30, %0" : "=r"(sp));
- memset(&r, 0, sizeof(struct pt_regs));
- r.iaoq[0] = (unsigned long) current_text_addr();
- r.gr[2] = (unsigned long) __builtin_return_address(0);
- r.gr[30] = sp;
- unwind_frame_init(&info, current, &r);
+ unwind_frame_init_task(&info, current, NULL);
/* unwind stack */
- ++level;
+ level += 2;
do {
if (unwind_once(&info) < 0 || info.ip == 0)
return 0;